|Publication number||US8083236 B2|
|Application number||US 12/564,521|
|Publication date||Dec 27, 2011|
|Filing date||Sep 22, 2009|
|Priority date||Sep 22, 2009|
|Also published as||EP2305957A2, EP2305957A3, US20110068540|
|Publication number||12564521, 564521, US 8083236 B2, US 8083236B2, US-B2-8083236, US8083236 B2, US8083236B2|
|Inventors||Darryl A. Colson, Craig M. Beers|
|Original Assignee||Hamilton Sundstrand Corporation|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (20), Referenced by (1), Classifications (8), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present application is directed to an improved labyrinth seal design, and more specifically to a labyrinth seal design which hybridizes known straight through seal designs and known staggered seal designs.
Air flow management machines such as fans, turbines, and compressors typically have rotating air seals which separate areas of high fluid pressure and low fluid pressure within the machine. As a result of the rotation, it is not possible to create a perfect seal which prevents 100% of the leakage which could occur between the high pressure area and the low pressure area. The path which the fluid travels when it leaks from the high pressure area to the low pressure area is referred to as the “leakage flow path.”
In order to reduce the amount of fluid which can flow across the leakage flow path, two types of seals have been used in the prior art. The first type of seal uses a straight leakage flow path and is referred to as a straight through seal. The straight leakage flow path has a large amount of leakage relative to other types of seals. However, it is easy to assemble and is constructed out of significantly simpler and cheaper components than other known seals.
The second type of seal used in the prior art is a staggered seal. The staggered seal creates a flow path which is significantly more restricted than the flow path of a straight through seal. The staggered seal uses a series of fins on the static element and a series of fins on the rotating element within the seal. The fins alternate, with each fin from the rotating element being adjacent to two fins from the static element. This forces the leakage flow path to travel a more complex, winding, pathway and results in a decrease in pressure leakage between the high pressure area and the low pressure area, relative to the straight-through design, due to the leakage flow path being throttled.
The staggered seal design is significantly more complicated to construct, as the fins must be arranged in the correct pattern and have a tight tolerance. The staggered seal additionally uses more expensive components and a greater quantity of components. These two features combined result in the staggered seal assembly costing significantly more to manufacture and assemble than other less complicated seal designs.
Disclosed is a seal assembly having a rotating element contained within a static sealing element. Adjacent to the static sealing element is a staggered element, which also surrounds the rotating element. The static element has at least one fin, which extends radially inward toward the rotating element, and the rotating element has at least one fin, which extends radially outward from the rotating element. The staggered element has at least one fin, which extends radially outward from the rotating element, toward the static element.
Also disclosed is a cylindrical seal having a plurality of notches and at least one fin. The seal is cylindrical with an interior through hole extending axially through the cylinder.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
As an alternate to the straight through seal illustrated in
As can be appreciated from
The static element 210 and the shaft 212 separate the high pressure side 202 from the low pressure side 204 through the use of several fins 310, 320, 330, 340. The shaft 212 has a first shaft fin 310 and a set of second shaft fins 320. The first shaft fin 310 extends farther away from the shaft 212 and into a notch 350 of the static element 210. The set of second shaft fins 320 extend away from the shaft 212 toward the static element 210 along a center portion 352 of the static element 310. The static element 210 has a static fin 330, which extends radially inward from the static element 210 toward the shaft 212. Adjacent to the static fin 330 is a staggered element fin 340. The staggered element fin 340 extends radially outward from the shaft 212 into a second notch 354 of the static element 210, and is connected to the impeller 240. In alternate applications the staggered element fin 340 could be attached to any component, which is adjacent to the high pressure side 202 of the static element 210, and which rotates along with the shaft 212.
The static element 210 is radially thinner in the notches 350, 354 than in the center portion 352. This allows the fins 310, 320, 330, 340 to create a staggered leakage flow path (illustrated in
Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.
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|Citing Patent||Filing date||Publication date||Applicant||Title|
|US9086131||Jan 24, 2013||Jul 21, 2015||Silver Ii Us Holdings, Llc||Gearbox output seal|
|U.S. Classification||277/418, 277/419, 277/420|
|Cooperative Classification||F05D2220/40, F01D11/02, F16J15/4472|
|Sep 22, 2009||AS||Assignment|
Owner name: HAMILTON SUNDSTRAND CORPORATION, CONNECTICUT
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:COLSON, DARRYL A.;BEERS, CRAIG M.;REEL/FRAME:023267/0255
Effective date: 20090922
|May 29, 2015||FPAY||Fee payment|
Year of fee payment: 4